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EA Series Head discussion.


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Ok, so I need some information inreguards to THIS topic and thought this would be the better place to discuss the differences & whatnot.

Basically, I need to know if that idea is at all do-able. Surely someone in this pool of knowledge has delved into this idea before?

Does anyone even have a few ea81 & ea82 heads to compare?

I understand the ea82 valves are around the other way to the ea81 which would require a different cam, similar idea to that found in the dualcarb ea81's.

Discussion please as I think this would be one of the better routes for an engine for me to follow.

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I think this may qualify him for the looney bin

 

ea81t is IN BLOCK CAM

EA82T is overhead cam to be correct dual overhead cam

 

head and intake gaskets are wrong shape

 

ea81t SINGLE PORT INTAKE

EA82T dual port intake

 

you would be better off using subaru heads on a vw air cooled, which has been done

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Ok, this is some progress. When I quizzed him on the slight difference of the whole ohv & ohc issue. He said that the ea82 heads, minus all the ohc parts, with some holes machined in them (where there were already allowances) for the pushrods, and the ea81 lifters, rockers etc bolted on, would work. Then an ea82 intake manifold.

Does that make any more sence?

Are the headbolts in anywhere near the same places?

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coolant passages are different

http://www.autohausaz.com/search/model.aspx?makeid=SU&year=All

ea82 has two cams, one on left and other on right , which makes it DOHC

 

No my friend, you are mistaken. While Yes, the EA82 and EA82T both have a cam in either head, it is still a single overhead cam. The designation is given because the engine has a single camshaft that operates both the intake and exhaust valves in the cylinder head. If it had a seperate intake and exhaust camshaft in both heads, THEN and only then would it be designated a dual overhead cam(DOHC) engine. Even if the engine in question were a V8 with a seperate intake and exhaust camshaft, it would still be called a DOHC.

 

-Patrick

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Right so we've cleared up what is sohc and what is not.

If I had some ea82 parts other than a rusted tubro block (which is currently only good for an anchor) I would look myself, But I do not have these parts (yet), and have never heard of this idea, so I am calling on someone that might know/can find out 100%

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Nevermind, just found the info on another thread on page 2...

 

Dean.

Right so we've cleared up what is sohc and what is not.

If I had some ea82 parts other than a rusted tubro block (which is currently only good for an anchor) I would look myself, But I do not have these parts (yet), and have never heard of this idea, so I am calling on someone that might know/can find out 100%

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SO ... then you have twin dual over head cam TDOHC.....

call it what you will

this is incorrect. the EA82(T) is a SOHC engine.

 

is there a reason for fitting an EA82 head to an EA81? RAM engines makes dual port EA81 heads, why not go that route?

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this is incorrect. the EA82(T) is a SOHC engine.

 

is there a reason for fitting an EA82 head to an EA81? RAM engines makes dual port EA81 heads, why not go that route?

 

Because RAM askes quite a bit of money for them and if you have acces to proper machines and some heads you can do all this for yourself on 1/10th of the budget.

 

And something else comes to mind, people often do things because it hasn't been tried before, even if it doesn't make sense. If nobody did this we wouldn't be swapping EJ22's in our EA cars now ;)

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Because RAM askes quite a bit of money for them
i agree, that's why i never mentioned buying them, i assumed he would make them if he's talking custom EA head work anyway.
RAM engines makes dual port EA81 heads, why not go that route?
people often do things because it hasn't been tried before
or for power, or reliability, or those are the parts they have, or cost, or....there's lots of reasons, all are good ones, i'm trying to figure out what his is. questions are easier to answer if the final goal is known. an EJ swap is different, the goals are obvious. huge power gains, lots of after market support, turbo upgrade options, reliability, easy to find parts, cheap parts....etc. if it is "just to do it", that's great - then we know the final goal which helps answering questions.
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its worth looking at, i mean, the head bolts hold in the rockers on an ea81, so they would probably bolt onto an ea82 head, with or without machining.

cams can always be ground differently

i think dual port ea82 heads on an ea81 would be cool. you could use the ea82 mpfi manifold, machine the center to fit a carb, then the coolant passages between heads are away from the intake ports, drill 4 holes for pushrods,...

subaru didnt invent the wheel with the ea82, its just another generation of the ea81.

having said that, i think dual intake ports on a ea81 head wont be very hard to do, exhaust is alot harder as far as i can see.

i've got a super sweet ea81 going together! i cant wait to see what kind of power i can get out of it

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Yes, now we've gotten past what is Dohc and what is Sohc.

I mostly would like it if someone who has the two could give me a definate reply on what will and will not work.

In short, the plane bloke seemed pretty adament it would work, and everywhere I could try and pick holes in his plan, he could come up with an answer, But I wanted some definate answers before I went buying some ea82's (god forbid...I kid)....

His aim, was to create an ea81t. These are not easy to come by here, let alone in good condition. EA82t's are plentyful, ea81's are common as dirt.

My aim, is to create something better than an ea81, have not decided whether FI is the way yet, just gathering info.

So I understand the ea82 bore and stroke is the same as the ea81, so if the ea82 heads were to fit on the ea81, the ea82 intake in theory should still fit right?

 

I don't mind if this idea is dis-proven, but would like to have it heard out first as it seems like a good option IMO.

Also, please keep it ON topic if you could. Pictures of any EA Series heads would be good to compare pleeeease.

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obviously you've already considered this, what's up with EA81T parts or swapping to an EA82T? shipping, availability or cost is prohibitive?

 

I don't mind if this idea is dis-proven.
it is possible, i worked at NASA, some fairly amazing things can be done. the question has nothing to do with possible and everything to do with resources! i know someone making his own heads from scratch....that's another option if resources are at your disposal.
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EA81T's aren't exactly plentyful over here, and far from ideal in their stock form from what I gather?

EA82T's are a bit more easy to get a hold of, but for an Aircraft guy, pushrods seem to be more popular due to the lack of cambelts.

For me, its just to get something close to the dualcarb ea81 at the moment, & I believe ea82's don't fit in Gen 1 vehicles & I like ea81's....

I have some resources available to me, not much more than a laythe and a few other bits and pieces, I'm assuming Mr Aeroplane I talked to had a bit more on hand.

The way he put it to me, was that an ea82 head will 'bolt' straight onto an ea81 block very easily, the ea81 valve gear worked very easily on the ea82 head, with only needing to machine a few holes for the lifters where there were already 'castings' (for want of a better word).

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sounds good. i'm kind of surprised a couple people haven't chimed in on this yet? i don't have any EA stuff on hand to look at.

 

could you go to your parts store and compare the headgaskets to both? might not answer your questions, but might be worth a look? i have EA82 headgaskets lying around. i'm not against stopping at a store to over-lay them on EA81 head gaskets. would that help at all?

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As am I, If its as easy as the plane guy makes out, It should be... well, easy.

Comparing headgaskets would help clear up a bit, not sure if any parts stores round here would actually stock HG's for the ea series though.

The only ea82 bits I have is a buggered block, putting some ea81 heads against it could shine some light, but is hardly ideal.

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EA81T's aren't exactly plentyful over here, and far from ideal in their stock form from what I gather?

 

They are just fine in their stock form, and I have most of my spare one in parts in my garage which I would consider parting with. Can't quite remember what is and isn't there, but I'll check it out if you are interested...

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it almost works! the ea82 head fits on the ea81, the coolant passages line up, there are two pushrod holes that are still there in the ea82 head, and two that arent, the problem is that the "oil jacket?" doesnt quite match up, i'll post pics in a few minutes, but this has realy got me thinking!

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now im getting excited.

water jackets all match up, there are already two holes for the two outer pushrods, and there looks like there is just enough room for the two center pushrod holes.101_0540.jpg

101_0539.jpg

 

 

heres a pic of the one spot on the block that wont match up, im thinking about machining a square chunk out of the ea82 head and welding in a little aluminum to seal up the oil passage to the head

101_0552.jpg

101_0549.jpg

101_0541.jpg

 

 

i think id have to run gutted ea82 rocker boxes to seal up the ea81 rocker arms

101_0551.jpg

101_0550.jpg

101_0548.jpg

101_0547.jpg

101_0546.jpg

101_0545.jpg

101_0544.jpg

101_0543.jpg

101_0542.jpg

101_0540.jpg

101_0539.jpg

 

 

looks like the rocker arms will bolt right on, but i think im going to weld in a chunk of aluminum to give them a wider place to mount, and put in two studs like the ea81 has...

this is super sweet, i was hoping they would bolt right on and seal up, but with a little machining, its going to work

 

 

the ea81 head is real clean, the ea82 head is the dirty one.

 

this must have been an aaftermarket gasket, you can see how two holes in the water jacket were covered up, but its the same jacket on both heads.

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